Known in the prior art are devices for fixing such injectors where the injector is held in place on the bottom of a casing, called shaft, in a lower side of the cylinder head, by a sliding collar attached by screws to an upper part of the cylinder head. This collar surrounds the body of the injector and rests on the protruding part of a snap ring mounted in a peripheral groove of the body of the injector.
The major drawback of such devices resides in the fact that the area where the body injector is held in place by the collar is relatively far from the support side of the injector on the bottom. This can cause the body of the injector to buckle, which negatively affects its reliability. Furthermore, since the collar is fixed on the accessible upper side of the cylinder head, such a device causes an upward congestion of the main injector.
Also know is a device that makes it possible to extenuate the afore-mentioned inconveniences, as described in particular in DE 43 15 233, in which the means of fixation are integrated in the cylinder head, in a chamber that contains the mechanical components that activate the valves and consist of a cylinder liner that surrounds the injector body and assures support on the snap ring located on the injector relatively close to the bottom of the shaft. This liner is attached to the cylinder head by a yoke that rests on two external transversal liner wings under the tightening action of a screw in the cylinder head.
Such a device requires relatively complex and costly means of tight shutoff and requires that the injector be dismantled which is quite difficult, in particular when the cylinder head is equipped with a camshaft that passes through its upper part.
The object of this invention is to propose a device similar to the one described above and that remedies the above-mentioned inconveniences.
With this end in view, the object of this invention is a device for fixing a fuel injector on the cylinder head of an internal combustion engine, on the upper face of which rests a camshaft holder that delimits with this face a chamber that contains mechanical components that activate the valves, where the injector passes through the camshaft holder and the cylinder head, and is held in place on the bottom of a shaft of the cylinder head by a yoke that is attached by a screw to the cylinder head, characterized by the fact that the yoke is located in the chamber under a camshaft and extends perpendicularly to this shaft.
According to a few interesting provisions of the invention:
the yoke consists of two branches that, in the operating position, rest on either side of the injector body on two wings arranged symmetrically on the periphery of the injector body; PA1 the branches demarcate between them a space that only lets the wings of the injector pass through when the latter is turned approximately a quarter turn in relation to its operating position; PA1 the injector body consists of a wide cylindrical section tightly held in a bore of the camshaft holder, with a diameter large enough to let the wings pass through; PA1 the camshaft holder consists, on the right of the retainer screw of the yoke, of a conduit that is large enough so a tightening tool for said screw can pass through; PA1 the shaft is made of a tube that is tightly attached to the cylinder head while passing through a chamber made in the cylinder head that contains a cooling liquid; PA1 the yoke and its screw are put in place, without tightening the screw, then the camshaft holder is is put on the cylinder head that has been previously equipped with valves and mechanical components for their activation, PA1 the injector body is inserted in an appropriate bore of the camshaft holder by setting the median axis of the wings of this body parallel to the branches of the yoke, until this injector rests on the bottom of the shaft; the wings will then be under the yoke, PA1 by means of the head of the injector, we perform a rotation of approximately one quarter turn of the latter in order to position the median axis of the wings perpendicularly to the branches, PA1 and the injector is fixed in the operating position obtained by tightening the retainer screw of the yoke.
Another object of this invention relates to a method for mounting a device for fixing a fuel injector consistent with the device described above, characterized by the fact that: